docs: def section_radial_distances(neurites, neurite_type=NeuriteType.all, origin=None,
                               iterator_type=Tree.ipreorder):
      '''Section radial distances in a collection of neurites.
      The iterator_type can be used to select only terminal sections (ileaf)
      or only bifurcations (ibifurcation_point).'''
      dist = []
      for n in iter_neurites(neurites, filt=is_type(neurite_type)):
          pos = n.root_node.points[0] if origin is None else origin
          dist.extend(sectionfunc.section_radial_distance(s, pos)
                      for s in iter_sections(n,
                                             iterator_type=iterator_type))
      return dist